PDF Library for Delphi Automatic Font Fallback for CJK and Emoji Text
Fix missing CJK, symbol and emoji glyphs in Delphi PDFs using PDF Library for Delphi font fallback, cluster-aware shaping and a JSON missing-glyph report
Software Development Blog
Delphi PDF Library
Delphi PDF Library: PDF Library for Delphi programming guides and examples
Automatic Structure Tagging for Accessible PDF in Delphi
PDF Library for Delphi tags text, headings, figures and tables while you draw, so accessible PDF output no longer means hand-wrapping calls in BeginTag
Embed AVIF, HEIF and JPEG XL Images in PDF from Delphi
PDF Library for Delphi embeds AVIF, HEIF and JPEG XL images in PDF, keeping the alpha, ICC profile and 16-bit channels that a bitmap conversion loses
Barcodes in PDF With Delphi: QR, PDF417, DataMatrix
Vector barcodes stay crisp at any size. See how PDF Library for Delphi draws QR, PDF417, DataMatrix and Code128 in Delphi, with error correction and sizing
Delphi TIFF Decoder Hardening: BigTIFF and Tiled TIFF
How PDFlibPas hardened its built-in Delphi TIFF decoder: BigTIFF magic 43 named and refused, tiled TIFF declined at tag parse and decodes capped at 256 MiB
Catalog SpiderInfo Web Capture Commands in Delphi PDFs
Write PDF Catalog SpiderInfo Web Capture command metadata in Delphi with PDF Library for Delphi: indirect command dictionaries, URL, levels, flag whitelist
Emailing PDFs via CDO in Delphi: Apartment-Threading Gotchas
PDF Library for Delphi emails PDFs from Delphi over Windows CDO, where correct CoInitializeEx apartment handling keeps multi-threaded batch sends alive
Collating Duplex Scans in Delphi: Interleaving PDFs
Merge front and reverse-side scan PDFs into reading order using PDF Library for Delphi CollateDocumentsEx in Delphi, interleaving pages without duplicate fonts
Compliance and Signing Workbench in Delphi
Wire PDF/A preflight, PAdES signing and ByteRange audits into one Delphi workbench with PDF Library for Delphi so the revision you validate is the one you sign
PDF Library for Delphi Content Streams: CTM and Clip-State Tracking
Replay a PDF content stream in Delphi with PDF Library for Delphi and track the CTM, text matrix, clip bounds and q/Q graphics-state stack per operator
Converting a PDF to PDF/A and Repairing Its Metadata
ConvertToPDFA repairs a document, states the part it claims and checks the result, while RepairDocumentMetadata makes Info and XMP agree in Delphi
Cross-Document PDF Object Copy in Delphi: Cycle Crashes
How PDFlibPas CopyForeignObject deep copies a PDF object closure across documents, and why cyclic Parent back references crashed until an in-progress guard
Export TDataSet and Reports to PDF in Delphi
Export any TDataSet, FastReport, QuickReport or ReportBuilder report to PDF in Delphi using losLab PDF Library, with paginated tables and headless output
Deterministic PDF ID in Delphi for Reproducible Builds
Make Delphi PDF output byte identical with a deterministic trailer ID: how the seed is derived, why encrypted files keep theirs, and what else to pin
PDF DLL, ActiveX and dylib Bindings in Delphi
PDF Library for Delphi exposes one flat PDF API as a Stdcall DLL, Safecall ActiveX object and Cdecl dylib, and the string and handle traps each binding hides
PDF Lifecycle Actions: Catalog /AA vs Page /AA in Delphi
PDF Library for Delphi attaches WillClose and WillPrint document actions to the Catalog /AA and page actions to the Page /AA in Delphi, within PDF/A limits
Ed448 and Brainpool ECDSA in Pure Pascal for PDF
How PDFlibPas implements RFC 8032 Ed448 and the three RFC 5639 Brainpool curves without an external crypto library, and the six root causes found along the way
Validating E-Invoices: veraPDF and Mustang in Delphi
PDF/A compliance is not invoice compliance. See how PDF Library for Delphi e-invoices pass both veraPDF container checks and Mustang business rules in Delphi
Embed Missing Fonts in Existing PDFs for PDF/A in Delphi
Fix PDF/A preflight error 00030 in Delphi: EmbedMissingFonts in losLab PDF Library appends font programs to existing PDFs without rebuilding font dictionaries
EMF Vector Import on Free Pascal With PDFlibPas
Why a 6500-line EMF to PDF converter needed a changed conditional, not a rewrite, and how a ULONG_PTR hatch field misaligns metafile records on Win64
Retrying Encrypted PDF Passwords in Delphi with PDF Library for Delphi
PDF Library for Delphi retries a wrong PDF password in Delphi by recreating TPDFDocument on each attempt rather than resetting it, and stops after sixteen tries
Auditing PDF Encryption and Permissions in Delphi
Read the PDF /Encrypt dictionary like an auditor with PDF Library for Delphi: algorithm, key length, AES-256 R5 vs R6, permission bits and Identity filter traps
Factur-X and ZUGFeRD Hybrid Invoices in Delphi
An e-invoice is a PDF/A-3 with invoice XML embedded inside. See how PDF Library for Delphi builds Factur-X and ZUGFeRD hybrid invoices across profiles in Delphi
Fast PDF Merge in Delphi: Byte-Level Ref Shifting
How PDF Library for Delphi merges PDFs quickly in Delphi by reusing source bytes and shifting indirect references object by object, skipping reserialisation
FDF, XFDF and XFA Form Data Interchange in Delphi
Move PDF form data between AcroForm and business systems in Delphi with losLab PDF Library: FDF and XFDF values, hierarchical fields, rich text and XFA XDP
PDF File Size Audit in Delphi: Byte Breakdown by Category
How AuditDocumentSpace in losLab PDF Library breaks a PDF file size down into 12 object categories in Delphi, so you measure bloat before you compress it
PDF Library for Delphi Form XObjects: Cycle Detection in Delphi
PDF Library for Delphi EnumPageContentStatesEx traverses PDF Form XObjects in Delphi, detecting call-chain cycles and scoping resource names per invocation
FPC Win32 OMF to COFF Object Linking in PDFlibPas
Free Pascal on Win32 needs COFF objects, so PDFlibPas keeps a separate object set, normalises section names and drops the Delphi 64-bit integer helper ABI
GeoPDF in Delphi: Geospatial Coordinates With PDF Library for Delphi
A PDF can carry the coordinate system of a map. See how PDF Library for Delphi reads GeoPDF viewports, measure dictionaries and WKT or EPSG frames in Delphi
GoToR, GoToE, and Launch Actions in Delphi PDFs
Build GoToR, GoToE and Launch actions in Delphi with PDF Library for Delphi: remote page jumps, embedded PDF targets, external launches and the zero-based trap
Flexbox, CSS Grid and Footnotes in PDF from Delphi
PDF Library for Delphi lays out HTML with display flex and grid inside PDF pages and paginates footnotes across columns and pages with continuous numbering
PDF Library for Delphi Hyphenation and Balanced Text Columns in Delphi
Set PDF text in balanced columns with language-aware hyphenation in Delphi, driven by PDF Library for Delphi DrawTextFlowColumns and SetTextFlowHyphenation
PDF Incremental Updates in Delphi: AppendToStream Guide
Write ISO 32000-1 incremental updates in Delphi with losLab PDF Library's AppendToStream: preserve digital signatures and skip full rewrites of large PDFs
OnExit Reentrancy in a Delphi In-Place Form Editor
PDF Library for Delphi TPDFlibViewer commits in-place form edits on OnExit; nil FInplaceEditor first or a focus loss re-enters the commit and corrupts data
Interactive PDF Forms in Delphi: Actions and JavaScript
PDF form actions turn a static page into an app. See how PDF Library for Delphi wires Hide, ImportData, Named and JavaScript actions onto fields and links
Build an Interactive PDF Viewer in Delphi with TPDFlibViewer
Build an interactive PDF viewer in Delphi VCL with TPDFlibViewer: five mouse tools, ready-made actions, search hit highlighting, annotation clicks and printing
JBIG2 Encoder Backends and the Free Pascal Linker
PDFlibPas offers a native Pascal JBIG2 encoder and an optional external one, and moving that external backend to Free Pascal required a DLL, not objects
Statically Linking jbig2enc into Free Pascal Without a DLL
PDFlibPas links the jbig2enc backend into Free Pascal executables without a DLL, while ObjConv clears pick-any COMDAT and FPC error 200603061
Merge and Split Gigabyte PDFs in Delphi with PDF Library for Delphi
Open gigabyte PDFs in milliseconds with PDF Library for Delphi direct access: page handles, streaming merge lists, range extraction and xref repair in Delphi
LZW EarlyChange in Delphi: Encoder Leads the Decoder
The LZW encoder dictionary leads the decoder by one entry, so the two sides cannot share a code width threshold, and PDFlibPas derives both from EarlyChange
PDF Garbage Collection in Delphi: Mark and Sweep
Why deleting PDF pages does not shrink the file, and how mark-sweep garbage collection in Delphi drops orphaned objects using the trailer root set
Memory-Mapped PDF Reading in Delphi: Sliding Window
PDFlibPas maps gigabyte PDFs through one sliding read-only window, so LoadFromMappedFile serves Delphi object slices without seek traffic or extra buffers
Merging PDF Forms in Delphi: Duplicate Field Rules
PDF Library for Delphi merges AcroForm documents with an explicit duplicate field policy that rejects, shares or renames same-named fields safely
ML-DSA in Delphi: FIPS 204 Post-Quantum in PDFlibPas
PDFlibPas implements FIPS 204 ML-DSA 44, 65 and 87 in Object Pascal for Delphi and FPC, covering the shared engine and the sampling bugs that broke the KAT
Classifying What Changed in a PDF After It Was Signed
PDFlibPas compares a document against an earlier revision and sorts every difference into a whitelist, so DocMDP enforcement becomes a single level comparison
Render PDF Pages to 1-Bit Monochrome in Delphi
Render PDF pages to 1-bit monochrome bitmaps and clip a sub-region in Delphi with PDF Library for Delphi, with GDI halftone down-conversion outside the renderer
Multi-Engine PDF Rendering in Delphi
Switch between built-in, Cairo and PDFium renderers per file in PDF Library for Delphi: engine probes, DPI scaling traps and a fallback chain that logs itself
PDF Object Streams and Cross-Reference Streams in Delphi
How losLab PDF Library writes PDF 1.5 object streams and xref streams from Delphi: ObjStm layout, type-2 entries, W field widths and encryption rules
PDF Layers in Delphi: Optional Content Groups (OCG)
PDF layers drive maps, CAD drawings and multilingual variants. See how PDF Library for Delphi builds and reads Optional Content Groups and their configs
Read PDF Bookmark and Annotation Actions in Delphi
Most Delphi PDF libraries write bookmark and annotation actions but cannot read them back. PDF Library for Delphi introspects GoTo, URI, Launch and JavaScript
PAdES Digital Signatures in Delphi
Produce PAdES B-B, B-T and B-LT signatures with PDF Library for Delphi: timestamp reservations, DSS assembly and ByteRange audits before trusting a file
Page-Level Associated Files in PDF 2.0 with PDFlibPas
PDFlibPas binds embedded files to a single page through the AF array in ISO 32000-2 14.13, keeping the payload in the EmbeddedFiles name tree
Page Stitching and Watermark Templates in Delphi PDFs
Stitch PDF pages side by side or overlay them with vector fidelity using losLab PDF Library Form XObject capture and composable watermark templates in Delphi
Parallel PDF Page Rendering in Delphi: Thread Safety
Render PDF pages in parallel from Delphi with losLab PDF Library: why TPDFlib needs one instance per worker thread, CoInitialize for GDI+, and safe logging
Reduce PDF File Size in Delphi: Fonts, Images, LZW
Cut PDF file size in Delphi with losLab PDF Library: subset embedded fonts, downsample oversized images, and convert legacy LZW streams to Flate in one pass
PDF to Markdown and DOCX in Delphi with PDF Library for Delphi
Export PDF pages as semantic Markdown or editable DOCX from Delphi with PDF Library for Delphi: inferred headings, lists, tables and streaming writes
PDF/A and PDF/UA Preflight in Delphi with PDF Library for Delphi
Run PDF/A and PDF/UA preflight inside Delphi with PDF Library for Delphi: structured findings, diffable reports, save-time fixups and veraPDF cross-checks
PDF/A-3 Extension Schemas for Factur-X XMP in Delphi
A Factur-X invoice fails veraPDF when its XMP properties are undeclared. See how PDF Library for Delphi adds the PDF/A-3 extension schema for fx metadata
PDF/E-1 Engineering Documents in Delphi with PDFlibPas
PDF/E-1 has its own XMP namespace, demands full lifecycle metadata and forbids the BX compatibility escape, so PDFlibPas preflights content within bounds
PDF/UA Font Audit in Delphi: Widths, CharSet, CIDSet
How PDFlibPas audits PDF/UA font layers in Delphi: glyph widths resolved via cmap and CIDToGIDMap, conservative CharSet and CIDSet rules, content stream scans
PDF/VCR-1 Template Placeholders in Delphi with PDFlibPas
PDFlibPas builds PDF/VCR-1 replacement templates as a StructTreeRoot branch, so the save gate and the manifest walk every top-level branch, not only the first
Shrink PDFs by Merging Near-Identical Images in Delphi
PDF Library for Delphi merges visually identical PDF images that differ only in encoding, using perceptual hashing with three error thresholds and a dry run
Print Preview and Device-Context Output in Delphi
Delphi print preview that matches the printed page: device-context rendering, virtual printers, scaling, and DevMode persistence with PDF Library for Delphi
PDF Library for Delphi Performance Profiling: Hash Indexes in Delphi
Profile PDF rendering in PDF Library for Delphi: swap linear dictionary scans for hash indexes, per-pixel gamma maths for a LUT and quadratic joins for builders
Progressive PDF Range Loading in Delphi with PDFlibPas
How PDFlibPas opens multi-gigabyte PDFs from HTTP range servers and object storage: read callbacks, chunk-aligned caching, request coalescing and prefetch
Open Encrypted PDFs with a Raw File Key in Delphi
PDF Library for Delphi opens AES-128 and AES-256 PDFs from a hexadecimal file encryption key, verifies it against /U or /Perms, and keeps the handle read-only
Rebuild Damaged PDF Xref Tables: Delphi Recovery Scan
How the PDF Library for Delphi Delphi PDF Library rebuilds a damaged xref table with a single pass token scanner that ignores strings, comments and stream bytes
Converting a PDF to One Colour Space in Delphi
RecolorDocument moves a PDF into grey, RGB or CMYK without redrawing it, converting colour operators, images, indexed palettes and gradient stops together
Replacing PDF Pages in Delphi Without Breaking Bookmarks
Replace PDF pages in Delphi with PDF Library for Delphi while keeping page object identity, so bookmarks, links and form widgets still work after the swap
SASLprep AES-256 PDF Passwords in Delphi with PDF Library for Delphi
Non-ASCII AES-256 PDF passwords fail in other readers without SASLprep. How PDF Library for Delphi prepares passwords per ISO 32000-2 and RFC 4013 in Delphi
Self-Signed Test Certificates in Delphi with CryptoAPI
Generate self-signed RSA test certificates in Delphi with PDF Library for Delphi and Win32 CryptoAPI, covering CryptGenKey length flags and CRYPT_EXPORTABLE
SHAKE256 XOF in Delphi: Keccak Domain Separation
PDFlibPas runs SHA-3 and SHAKE256 on one Keccak-f[1600] core, differing only in the pad10*1 domain byte and the rate rule, and ships a streaming XOF for Delphi
Diagnosing Silent Stub Failures in a Pascal PDF Library
Three shapes of empty substitute implementation, why the one that reports success is the hardest to find, and how to diagnose it by inspecting output bytes
Soft Masks and Transparency Flattening in Delphi
PDF Library for Delphi authors alpha and luminosity soft masks, sets image Matte entries, and flattens transparency to a printable PDF 1.3 file
Tagged PDF Structure Trees in Delphi with PDF Library for Delphi
Generate tagged PDFs from Delphi with PDF Library for Delphi: structure trees whilst drawing, table header semantics, artefacts and PDF/UA checks before saving
Map PDF Text to Content-Stream Bytes in Delphi
PDF Library for Delphi maps every extracted character back to its content stream instruction and source bytes, so Delphi code can edit one glyph in place
Delphi PDF Text, Image, and Font Extraction
Extract positioned text, original image streams and font metadata from PDFs with PDF Library for Delphi, plus extraction options for search and audit jobs
Delphi PDF Text Search with Hit Coordinates: PDF Library for Delphi
Search PDF text by page range in Delphi with PDF Library for Delphi: each hit returns its page and bounding rectangle, and every text block or image is listed
True PDF Redaction in Delphi: Delete and Sanitise
Real PDF redaction in Delphi with losLab PDF Library: RedactRegion deletes content-stream bytes while SanitizeDocument strips metadata, scripts, and actions
Unicode-Safe PDF Text Search in Delphi: NFC and NFD
PDF Library for Delphi matches canonically equivalent text so an NFC query finds NFD content, and keeps every hit on whole grapheme cluster edges
Hardening a Pascal PDF Parser Against Malicious Files
A PDF parser is an attack surface. See real integer overflow, out-of-bounds write, and unbounded recursion defects in font and image decoders, with the Delphi
Vector Graphics in PDF With Delphi: Paths and Gradients
A PDF is a full 2D vector canvas. See how PDF Library for Delphi draws paths, Bezier curves and axial gradients, with even-odd versus nonzero fill, in Delphi
Vertical Japanese and Chinese Text in PDF with Delphi
PDF Library for Delphi sets Japanese and Chinese text down the page through a Type0 font in vertical writing mode, using the vertical glyph forms of the face
PDF Viewer Disk Cache and Per-Monitor DPI in Delphi
Speed up a Delphi PDF viewer with a cross-session disk page cache and per-monitor DPI: FNV-1a fingerprints, LRU pruning and WM_DPICHANGED in losLab PDF Library
Web Fonts in PDF: WOFF2 and Variable Axes in Delphi
PDF Library for Delphi imports WOFF2 web fonts and instantiates TrueType and CFF2 variable axes into static fonts that embed, subset and extract normally
XFA SOM Path Expressions in Delphi: Dynamic Form Data
Fill repeating rows in dynamic XFA forms from Delphi using XFA 3.3 SOM path expressions in losLab PDF Library: $record roots, [*] occurrences and predicates